On Aug 3, 2004, at 4:19 PM, Andreas Raab wrote:

> It seems to me that we might be able to simplify this by saying we 
> have three
> major compatibility levels:
> * interface/semantics unchanged (known to be compatible) (5 and 6)
> * interface/semantics (expected to be) compatible (3 and 4)
> * interface/semantics (expected to be) incompatible (1 and 2)

+1